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Scientists have identified a certain protein that may protect against Alzheimer’s and potentially lead to a new drug to help fight symptoms of the brain disorder.

The protein is known as transthyretin (TTR), and acts as a transporter in the body, carrying vitamin A and a hormone called thyrozine through the bloodstream. Transthyertin is produced in the liver and certain brain regions. After years of research on the protein, scientists are finally discovering its anti-Alzheimer’s properties, according to a new study conducted by Professor Joel N. Buxbaum, of the Scripps Research Institute, and colleagues.

TTR began showing an ability to bind amyloid-beta, which is a protein found building up in the brains of people with Alzheimer’s, and prevent it from clustering together to form clumps, in the 1990s. Scientists noted that if the protein really did prevent amyloids from building up, TTR would be a potential key to preventing Alzheimer’s. “At the time it seemed unlikely that one amyloidogenic precursor would have a beneficial effect on the aggregation of another,” Buxbaum told Medical News Today. “The in vitro experiments were technically suspect, but turned out to be essentially correct.”

Despite his skepticism, Buxbaum conducted a study in 2008 to test the Alzheimer’s theory, and found that TTR actually did lessen the amount of aggregation of amyloid-beta in mice’s brains and boosted their memory. “Given that background, I was predisposed to be skeptical,” he told Medical News Today, “which was probably a good thing since it made me look at the data from our genetic experiments very critically. I figured if the results convinced me, they should convince anyone.” In a press release from 2008, Buxbaum notes that getting rid of the natural TTR protein in mice caused Alzheimer’s disease to arrive earlier and more intensely; when they added the human TTR protein, the symptoms ceased to progress and their conditions improved.

In the new study, Buxbaum and co-authors Xin Wang and Francesca Cattaneo investigated TTR further, and found that certain “transcription factors” could promote TTR production. “This result was completely unexpected when we started this research,” Buxbaum said. “But now we realize that it could indicate a new approach for Alzheimer’s prevention and therapy.” There are some five million people in the U.S. who suffer from Alzheimer’s disease, and this number is expected to increase to 16 million by 2050. As scientists attempt to find a cure or at least a treatment for the disease, Buxbaum hopes that his TTR research could eventually lead to a treatment in the form of a pill that would boost TTR production.